I am using ArcGIS for Desktop 10.3.1 with a basic license.
You have this posted in the ArcGIS Pro place... You might want to move it to Managing Data
In any event, there is a whole section on map templates
and from the first line
A map template is a map document (.mxd)
and mxt are existing templates which is fine, as long as it works, just save it where you need it
Retrieving data ...